Treatment of dye wastewater by in situ hybridization with Mg-Al layered double hydroxides and reuse of dye sludge

A multi-anion dye (e.g. direct blending scarlet D-GLN) can intercalate into Mg-Al-layered double hydroxides (LDHs) which is confirmed from XRD, SEM, FTIR, DTG and zeta-potential analyses. The DGLN-LDHs hybrid with the hybridization amount 524 mg/g DGLN exhibits a high adsorption capacity to cationic dyes, e.g. 1064 mg/g for victoria! blue B. The hybrid was used as a sorbent to treat cationic dye wastewater and the decoloration rate over 80% by adding only 5 g/dm(3). In addition, the resulting sludge was reutilized as a colorant filled in polymer materials and it exhibited the resistance to bleeding and fire. This work provides a new approach for the treatment of dye wastewater and reutilization of dye sludge. (C) 2011 Elsevier B.V. All rights reserved.